Typewriting machine



W. A. DOBSON.

TYPEWRITING MACHINE' APPLICATION FILED APR-13,1920

Patented May 23, 1922.

2 SHEETSSHEET I.

W. A. DOBSON.

TYPEWRITING MACHINE.

APPLICATION FILED APR.13,1920.

Patented; May 23, 1922.

2 SHEETS-SHEET 2.

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WILLIAM A. nonson, or HARTFORD, CONNECTICUT, AssIcNoR 'ro unnnnwoon TYPEWRITER WARE. I

COMPANY, OF NEW YORK, N. Y., A CORPORATION OF DELA- TYPEWRITING MACHINE Specification of Letters Patent.

Patented May 23, 11922.

Application filed April 13, 1920. Serial No. 373,618.

State of Connecticut, have invented certain new and useful Improvements in Typewriting Machines, of which the followlng is a specification.

The present invention relates to a silent key mechanism for typewriting machines; that is to say, to a mechanism by means of which a key may function to print a character and concomitantlyto actuate a ribbonvibrator, or to act on other mechanismsin typewriting machines, while nevertheless being silent in the respect that it is ineffective to cause letter-space movement of the platen relative to the printing point.

Often, particularly in certain languages, a letter or character should have a particular accent mark printed directly above it, or should be underscored; and if keys hearing such accent or other special characters are not disconnected from the letter space mechanism, the carriage must be back-set after one key is operated, to ermit both the letter and the accent key, or instance, to

print at the same point in the line.

Silent-key mechanism which obviates the necessity of such back-setting is not broadly new with the present invention. In the prior art, however, the silent-key mechanism generally involves actuation of the universal bar or its equivalent, and consequently involves the presence and operation of some special device, such that the universal bar, although actuated, is nevertheless disabled to effect letter-space movement.

An object of the present invention is, in a simple and reliable-manner, to render unnecessary any operation of the universal bar by the silent key, while still maintaining an operative connection between the silent key and mechanisms, other than the letter-space mechanism, which are ordinarily operated through the universal bar, and which it may be desirable or necemary to operate when the silent key is operated. Such a mechanism, for instance, is the ribbon-vibrating mechanism, as the same is found in the Underwood portable typewriting machine, as shown in the pending application of George W. Campbell, No. 240,000, filed June 14,

1918, (noiv Patent N 0. 1,37 0,281, dated March 1, 1921). In such a machine, each typebar may carry three characters and the platen frame has three case positions accordmg to that character on the type-bar which 1s to be printed; and in that machine the rlbbon not only moves with the platen between case-positions, but is vibrated at each type-stroke to bring its printing field, or the selected one of its printing fields, to the prlnting point. Thus,.it is there necessary that in printing an accent mark by the silent key, the ribbon-vibrator is operated. For purposes of illustration, the present invention is hereinafter described as applied to the mechanism shown in the aforesaid pendmg application,- and deals particularly with the manner, in which it is therein embodied to provide for operation of the ribbon-vibrator by the silent-key without operation of the universal bar, while nevertheless rendering the ribbon-vibrator impotent to actuate the silent key-lever and type-bar when the vibrator is actuated from the universal bar by the usual character keys.

Other features and advantages will hereinafter appear. 7

' In the accompanying drawings,

Figure 1 is a skeleton perspective front view of a front-strike portable typewriting machine, embodying the present improvements, viewed from the forward, upper lefthand corner, some of the parts being broken away. I

Figure 2 is a sectional side view, taken near the right-hand side of the machine.

Figure 3 is a top plan view of the silent; key mechanism and the parts in immediate relation thereto, the fralme being broken :away and other parts being eliminated for clearness.

Figure 4 is a detail View in side elevation, partly in cross-section showing the link and slip connection between the vertical arm, which is fast to the universal bar, and the horizontal lever which actuates the ribbonvibrator.

Character keys 15, when actuated, move key-levers 16 about a common fulcrum plate 17 supported on a cross-bar 18, extending between the sides 19 of a main frame 21. The key-lever 16, when actuated, moves against the tension of a spring 22 to swing a bell-crank 23 about a fulcrum 24 on a bracket 25 secured to a cross-bar 26, also extending between the sides 19 of the main frame. The bell-crank 23 pulls on a link 27 to swing a type-bar 28 about a fulcrum 30 to cause the types 31 to strike against the front side of a platen 32.

The platen is rotatably supported by a platen axle 33 on a carriage 34, which may be urged from right to left in the usual manner by a spring drum (not shown). To cause the carriage to move from one letterspace position to another, while typing, there is provided a universal bar 35, with which the key-levers 16 engage to swing said universal bar about the axis of a fulcrum rod 36 pivotally supported by brackets 37, one at each end thereof, secured to the (rose bar 18. The universal bar 35, when actuated, moves against the tension of suitable. return springs 38, and an upwardly-extending arm 39 thereof engages with a horizontally-disposed dog-rocker 40, to cause the latter to swing about pivots 41, forming a vertical axis for said dog-rocker, and also cause suitable dogs .to reciprocate between the teeth 42 of an escapement wheel 43, said escapement wheel being secured to a shaft 44 having a pinion 45 thereon which meshes with a feed rack 46 pivotally supported on the carriage 34 at 47. As the carriage is constantly urged from right to left, the escapement wheel is rotated step by step through the intermediary of said rack 46 and pinion 45 to effect letter-space movements of the carriage 34 by vibrating the dogs on the dog-rocker between the teeth of said escapement wheel. Stops 20 determine the normal position of the universal bar.

At each type-stroke, a ribbon 48 is moved into the path of the striking type-bars 28. This movement of the ribbon is effected by an upwardly-extending arm 50 fast on the rock-shaft 36 of the universal bar 35, which arm 50, as the universal bar is actuated, thrusts a connecting link 51 forwardly to rock an intermediate lever 52 about a pivot 53, the latter being in the form of a shouldered screw; said lntermediate lever having a portion 54 forming a vertical channel or slot 55, into which projects a stud 56 to swing a ribbon-vibrating lever in the form of a bell-crank 57 about its pivot, comprising a hub 58 on a shouldered screw 60 threaded into a front uide-rail 61 for the typewriter carriage. S aid ribbon-vibrating lever has a horizontally-disposed arm 62 projecting inwardly toward the middle of the machine, the free end of which engages with a stud 63 on a ribbon-vibrator 64 to move the latter upwardly to expose the ribbon 48 to the printing point. The stud 56 and channel 55 form a pin-and-slot or slip-joint connection between the parts of the ribbon mechanism mounted in the shift frame and the parts mounted in the main frame, so as to permit free movement of the shift frame from one case position to another While maintaining an invariable movement-transmitting connection for all case positions of the shift frame.

The ribbon may be fed from one to another of two spools 65 in any convenient manner during typing, and guided through suitable slots 66, in the ribbon-vibrator, into which it may be inserted through suitable openings 67 formed in guide bars 68 of said ribbon-vibrator.

To guide the ribbon-vibrator 64 in its movements to and aw from the printing point, there is provided a guide 70 secured to the front guide-rail 61, said guide 7 comprising two upwardly-extending fingers 71, which are partially surrounded by ears 72 on the ribbon-vibrator. To guide the lower end of the ribbon-vibrator, and thus prevent any sidewise movement. thereof while it moves up and down, the guide 70 is provided with a slot or groove 73, into which projects the inner end 74 of the stud 63 on said vibrator, Figure 2. The hub 58 on the ribbon-vibrator-lever forms a substantially broad bearing therefor, and thus prevents said lever from wiggling when actuated. Thus, the free end of said ribbonvibrator-lever guides the lower end of said ribbon vibrator against any accidental movement from the front to the back of the machine.

The intermediate lever 52 comprises a back 75, Figure 3, to which the U-shaped member 54 is rigidly secured. The back 75 has extending forwardly therefrom two ears 76 and 77 with a sufficient space between them, so that with the shouldered screw 53 they form a substantially broad bearing for said lever 52. The screw 53 has a reduced portion 78 threaded into a bridge 80 secured to the cross-bars 18 and 26 extending between the side plates 19 of the main frame.

The ribbon 48 comprises two fields, preferably, a black field 81. and a red field 82. Either one of these fields may be brought to the printing point during typing. This may be accomplished selectively, by changing the point of connection comprising a stud 83 between the link 51 and the intermediate lever 52 by means of a color-control lever 84, which has a finger-piece 85 projecting beyond a front plate 86, Figures 1 and 3, of the machine; the lever 84 being settable by said finger-piece to any one of three positions relative to an indicator plate 87 having marks 88, 89 and 90, indicating a black position, a neutral position and a red position, respectively, to which said lever 84 may be moved.

The control lever normally occupies the position indicated in Figure 3, where it is set to the black mark 88 and is effective to hold the connecting link 51 with its point of connection 83 near the outer end of the intermediate lever 52.

When it is desired to render the red field 82 of the ribbon effective, the finger-piece or handle 85 is moved to the red mark or indicator 90, thus swinging the control lever 84 about its pivot 91 to draw on a link 92 which is pivotally connected by a shouldered screw 93 to the connecting link 51. This swings the link 51 to bring the point of connection 83 thereof from its Figure 1 position, at one end of a slot 95, formed in the intermediate lever 52, to a position at the righthand end of that slot; thus the point of connection 83 of the connecting link 51 is brought nearer to the fulcrum 53 of the intermediate lever 52; and, consequently, the universal bar, which is actuated always through the same distance by the numeral keys, will be effective to swing the intermediate lever 52 through a greater angular distance about its fulcrum 53, thus imparting agreater angular movement to the ribbon-vibrating lever 57 to raise the ribbon-vibrator 64 through a greater distance and expose the red field 82 of the ribbon to the printing point. The upper end of the arm 50, extending from the universal bar, has secured thereto a block having horizontally-disposed ears 96 between which the link 51 is pivoted at 97 to swing easily in a horizontal plane.

To prevent overthrow of the ribbon when the red field thereof is vibrated to the printing point, there is provided a stop 99 with which the inner end 74 of the stud 63 on the ribbon-vibrator-lever engages. This stop may be secured near the upper end of the slot 73 in any convenient manner.

The pivot 91 of the control lever 84 may comprise a shouldered screw threadediinto an upwardly and forwardly-projecting arm 104 extending from the bridge 80 which forms a support for the intermediate lever 52 To nullify the effect of the universal bar on the ribbon-vibrator, so as to prevent the actuation of said vibrator during stenciling, the control lever 84 may be moved to the neutral mark 89, which is preferably white. This movement of the control lever is effective to move the point of connection or stud 83 to a central position in the slot 95 of the intermediate lever 52. It will be noticed that the slot 95 at this place is formed with a depression or enlargement 105, so as to permit the stud 83 to move idly back and forth when actuated by the universal bar 35, thus permitting the actuation of the typekeys 15 without actuating the ribbon-vibrator 64, and, consequently, the ribbon 48 remains ineffective during typing.

To maintain the control lever 84 in its black neutral or red positions to which it may be set, it is provided at its under side with a projection or rib 106 which may engage in notches 107, 108 and 109, respectively, Figure 3, in a suitable plate or returning device secured to the front plate 86; and the operating lever 84 is slightly flexible, so as to yield to permit the rib 106 to move out of on notch and into another when said lever is ifted to the different positions.

As shown and described in the abovementioned co-pending application No. 240,- 000, the platen 32 may be shifted by shift keys 115 and 116 from a lower-case position to a middle-case position and an upper-case position so that the types 117 and 118, respectively, may be caused to print.

. It will be seen by an inspection of Figure 2 that the carriage 34 travels on rollers 134 and 135 co-operating with the front guiderail 61 and a rear rail 136, respectively; both rails being secured to the shift frame 130. The carriage is held for traveling movements on said rails of the shift frame by a roller 137 engaging on the under side of the front guide-rail 61 and a finger 138 engaging on the under side of the rear rail 136.

As described in the aforesaid co-pending application, a suitable stop is provided to locate the platen 32 in its middle-case position, and when the platen is shifted to its upper-case position, this stop is rendered ineffective, and the platen may be located in its upper-case position by means of another stop.

It is desirable during case-shifting movements of the platen to shift the ribbon therewith, so as not to disturb the position thereof relative to the printing point of the platen. To do this, the ribbon-vibrator 64 and the ribbon-vibrator-lever 57 are preferably supported on the front rail 61 which is secured to the shift frame. Thus, the ribbon-vibrator 64 and the actuating lever 57 move with the shift frame, during a case-shifting operation, at which time the stud on said lever moves lengthwise of the slot 55, formed in the U-shaped member 54 of the intermediate lever 52, the latter, it will be remembered, being supported on the main frame. The vertical length of the U-shaped member 54 is great enough to permit the stud 56 to occupy three positions therein, corresponding to lower-case, middle-case and upper case positions of the platen.

To the mechanism thus far described, the silent-key device of the present invention is readily applied, and operates in combination therewith as follows:

A silent key 1.40 is carried by a lever 141, fulcrumed like the character-key-levers on the bar 17, and held in, and returned to, normal position in the same manner as the character keys by a spring 22. Like the character-key-levers, the lever 141 has a pin-andslot engagement at 142 to engage and swing a bell-crank L3 connected by a link 27 wit-h a type-bar pivoted at 30. The. types 31, 117 and 118 on this particular type-bar are any accent or other marks, for instance, those shown at 143, 144 and 145 (Figure 3), which are to be used in such relation to characters; written by the character keys that no letterspace movement of the carriage is desired between the writing of the selected mark 143, 144 or 145 and the writing of that character which such mark is to accompany. The case position of the platen frame determines which of the marks 143, 144 or 145 is written, and this in turn, as shown and described in the aforesaid co-pending application, may be detennined by operation of the shift keys 115 and 116.

If, however, there is to be no operation of the carriage-escapement mechanism, and no letter-space feed of the carriage upon the writing of an accent or other mark on the key 140 and before the writing of the accompanying character, then, in the mechanism shown, the universal bar 35 is not to be actuated upon depression of the key 140. The key-lever 141 is therefore devoid of the lug or offset 146 which is found on the character-key-levers 16 for effecting operation of the universal bar. Incidentally, this incapac-itates the ke 140 to operate the rib-- bon'vibrating mec anism in the manner in which the latter is operated by the character keys 15 through the universal bar 35, lever 50 and link 51; and, as operation of the rib;- bon-vibrator is desirable, another connect-ion is provided from the silent key-lever 141 to the vibiator-lever 52, as follows:

Pivoted at 147 on the lever 141 is a lever having an arm 148 which terminates in an car 149 overlying the upper edge of the lever 141, and an arm 150 which is engaged by a hook 151 on the lever 52. The hook portion 151 forms with the body portion of the lever 52 a slot which is wide enough to provide play and prevent binding of the parts on depression and angular movement of the lever 141, but which is nevertheless such that the lever 52 is swung forward about its pivot when the lever 141 is depressed. The ear 149 causes the arm 150 to move as a unit with the lever 141 at the proper time. A set screw 152, passing through the ear 149 and engaging the upper edge of the lever 141, may be provided to permit of accurate adjustment of the connecting arm 150 between the levers 141 and 52, as in assembling the parts. When the intermediate lever 52 is swung forward, by depression of a character key 15, the arm 150 merely rocksforward, and the arm 148 upward, on the pivot 147. Movement of the silent-key-lever 141 and its connected type-bar at such times is thereby avoided.

It has bee-n pointed out that operation of It is equally in point, however, that the universal bar be not operated from the lever 141 through the levers 150, 52, link 51 and lever 50. To preventthe latter, without, however, interfering with the operation of the lever 52 by the character keys 15, the following connection is provided between the link 51 and the lever 52.

The link 51 positively actuates the intermediate lever 52 in one direction only, that is to say, on the forward throw of the arm 50 when a key 15 is depressed. The return movement of the lever 52 upon release of the key 15 may be effected by a spring 154 coiled on the pivot 53 of the lever 52, and having one end thereof secured to the bridge support 80 and the other end to the lever 52.

Referring to Figures 1, 3 and 4, it will be noted that the link 51 has a wide, fiat portion terminating at a shoulder 155, beyond which the link continues in the form of a pin adapt-- ed to slide freely in a sleeve 156. The sleeve 156 is threaded into and through a boss 158, which is integral with the stud 83 forming the connection between the link 51 and the intermediate lever 52. A setscr ew 157 holds the sleeve 156 adjustably fixed in the boss 158. Abutment of the shoulder 155 with the end of the sleeve 156, on forward movement of the arm 50 when a character key 15 is depressed, results in movement of the boss 158 and stud 83 to swing the intermediate lever 52. On release of the key 15, the link 51 is drawn backby the arm 50, and the spring 154 causes the arm 52, boss 158 and sleeve 156 to follow the same. The threading of the sleeve 156 into the boss 158 and the set-screw 157 for fixing the sleeve is to permit of accurate adjustment of the levers in assembling, and of readjustment when necessary. A screw 159, passing through a washer 160 and into the stud 83, holds the latter in the slot 95 in the intermediate lever 52.

Since the boss 158 may slide freely outward and forward on the link 51, it follows that when the lever 52 is swung forward to vibrate th ribbon mechanism on depression of the silent key 140, there is no forward movement of the link 51, or movement of the universal bar and escapement mechanism connected thereto. The link 51 being pivoted at 97, and having a pivoted connection at the stud 83 to the lever 52, may, however,

have such angular movement as is necessary to prevent binding of the parts whenever arm 50 or lever 52 is actuated;

Variations may be resorted to within the scope of the invention, and portions of the improvements may be used without others.

Having thus described my invention, I claim:

1. In a typewriting machine; type and key-levers therefor; a ribbon-vibrator to be operated from each of a plurality of typekeys; a universal bar for such plurality of keys; a lever actuated by the universal bar; another lever for actuating the ribbon-vibrator; a link connecting said last two levers, said link having a sliding bearing in one of said levers and a shoulder for engagement therewith, whereby the link may be moved by the universal bar and, through said shoulder, may actuate the ribbon-vibrator lever in one direction, the sliding bearing permitting movement of the ribbon-vibrator-actiiating lever independently of the universal bar; and a separate key-lever ineffective on said universal bar but effective on the secondmentioned lever so as to actuate the latter without effecting longitudinal movement of said link.

2. In a typewriting machine; type and key-levers therefor; a ribbon-vibrator to be operated from each of a plurality of typekeys; a universal bar for such plurality of keys; a lever actuated by'the universal bar; another lever for actuating the ribbon-vibrator; a link connecting said last two levers which link has a sliding bearing in one of said levers and a shoulder for engagement therewith, whereby the link may be moved by the lever of the universal bar and, through said shoulder, actuate the ribbon-vibrator lever in one direction, the sliding bearing permitting movement of the ribbon-vibrator lever independently of the universal bar; a carriage; carriage-escapement mechanism actuable by said universal bar; and a separate key-lever ineffective on said universal bar but effective on the second-mentioned lever so as to actuate the latter without effecting longitudinal movement of said link and without actuating said escapement mechanism.

3. In a typewriting machine; a carriage and escapement mechanism therefor; type and key-levers therefor; a ribbon-vibrator to be operated from each of a plurality of type-keys; a lever for operating the ribbonvibrator; a two-armed rocker pivotally carried on one of the key-levers, one of its two arms being in engagement with the lever for operating the ribbon-vibrator, and the other of its arms engaging the key-lever which carries it, in such. a manner that the twoarmed rocker acts as a rigid connection to actuate the ribbon-vibrator lever from the carrier key-lever, but rocks idly on such carrier key-lever when said ribbon-vibrator lever is actuated by other key-levers; a de vice universal to said other key -levers; to actuate said ribbonvibrator lever and said escapement mechanism; and a slip connection between the ribbon vibrator lever and said universal device whereby the universal device is in positive engagement with the riblmn-vibrato'r lever for throw of the latter in one direction only, and the ribbon-vibrator lever may be moved independently of the universal device by said two-armed rocker, and typing effected without line-space movement of the carriage.

4. In a typewriting machine; a carriage and escapement mechanism therefor; type and key-levers therefor; a ribbon-vibrator to be operated from each of a plurality of the type-keys, which also actuate the escapement mechanism; a lever for operating the ribbon-vibrator; and a, two-armed rocker pivotally carried on one of the key-levers other than those that actuate the escapement mechanism, one of the two arms of said rocker being in engagement with the lever for operating the ribbon-vibrator, and the other of its arms engaging the key-lever which carries it, in such a manner that the two-armed rocker acts as a rigid connection to actuate the ribbon-vibrator lever from the carrier key-lever, but rocks idly on said carrier key-lever when said ribbon-vibrator lever is actuated by the other key-levers.

5. In a typewritlng machine, in combination, a carriage; a platen; a platen-frame shiftable in said carriage to effect caseshift; supporting means for said platenframe includin a case-shift rail; a ribbonvibrator; an elbow-lever pivotally mounted upon said rail and having an arm extending substantially parallel to said rail and connected with the ribbon-vibrator and a second arm substantially perpendicular to the first-mentioned arm; a lever carried by the frame of the machine and swingable about a vertical pivot; a connection between said last-mentioned lever and said perpendicular arm' of the elbow-lever, whereby shifting of the rail may be effected without altering the action of the second-mentioned lever on said elbow-lever; type-keys; an escapement mech- I anism for said carriage; a device universal. to certain of said keys; a connection whereby said universal devlce may actuate said escapement mechanism; a one-way connection whereby said device may actuate the second-mentioned lever; and a one-way connection between said second-mentioned lever and one of the type-keys, other than those effective on said universal device, whereby the ribbon-vibrator may be actuated without actuation of the escapement mechanism.

6. In a typewriting machine; type and key-levers therefor; a ribbon-vibrator to be operated from each of a plurality of typekeys; a lever for operating the ribbonvibrator; an arm carried by one of the keylevers, and in engagement with said ribbonis rocked; and means whereby, when other key-levers actuatethe ribbon-vibrator lever, said arm may be rocked on its aforesaid carrier key-lever by the ribbon-vibrator lever in engagement therewith Without actuating such carrier key-lever.

7. In a typewriting machine; type and key-levers therefor; a' ribbon-vibrator to be operated from each of a plurality of the type-keys; a lever for operating the ribbon-i vibrator; and a two-armedrocker pivotally carried on one of the key-levers, one of its two arms being in engagement with the lever for operating the ribbon-vibrator, and the other of its arms engaging the keylever which carries it, in such manner that the two-armed rocker acts as a rigid connection to actuate the ribbon-vibrator lever from said carrier key-lever, but rocks idly on said carrier key-lever when said ribbonvibrator lever is actuated by other keylevers.

8. In a typewriting machine; type and key-levers therefor; a ribbon-vibrator to be operated from each of a plurality of the type-keys; a lever for operating the ribbonvibrator; a two -armed rocker pivotally carried on one of the key-levers, one of its two arms bein in engagement with the lever for operating the ribbon-vibrator, and the other of its arms engaging the key-lever which carries it, in Such manner that the two-armed rocker acts as a rigid connection to actuate the ribbon-vibrator lever from said carrier key-lever, but rocks idly on said carrier key-lever when said ribbon-vibrator lever is actuated by other key-levers; a. device universal to said other key-levers for actuating said ribbon-vibrator lever; and a slip connection between the latter and said universal device whereby the universal device is in positive engagement with the ribbon-vibrator lever for throw of the latter in one direction only, and the ribbon-vibrator lever may be moved independently of the universal device by said two-armed rocker.

"5). In a t'ypewriting machine; type and key-levers therefor; a ribbon-vibrator to be operated from each of a plurality of the type-keys; a universal bar for such plurality of keys; a lever actuated by the universal bar; another lever for actuating the ribbonvibrator; and a link connecting said last two levers, which link has a sliding bearing in one of said levers and has a shoulder for engagement therewith, whereby the link may be moved by the lover of the universal bar, and through said shoulder actuate the ribbon-vibrator lever in one direction, the sliding bearing permitting movement of the ribbon-actuator lever independently of the universal bar.

WILLIAM A. DOBSON.

' Witnesses:

GEORGE W. CAMPBELL, M. S. EAKIN. 

